DIPTERA

451

II'
III

DIOPSID.*:.

produced into an

; no vibrissse ; front

Small, hare flies. easily by the of

the head. They have a restricted
have found in India, Africa, Xorth

Little Is known of these flies,, except
a short of which in given by Sen (1921). He

these forms are found in certain of

in swarms on or the in

shady places. Their structure suggests a habit,

but this not yet proved. In captivity the

of the egg was found to be four days, the
seven days, and that of the days. The struct lire of

the larva indicates a semi-aquatic mode of life.

They art* of no economic importance.

CORDYLURID.E.
Front with bristles ; eyes widely separated In both ;
squanue present, but small; suTbco&ta present; costa
pectinate or not* but never with a spine where Reruns into
the costa ; abdomen with mere than four visible segments.
The larva? are found in dung (mostly the sub-family
phagm&.)i in wet places near water, and. in the stems of water
plants. Williston, 19(18, records a species of as a
Noctuid parasite.
The adult flies are found in moist places and about excrement,
and are predaeeous. the yellow
fly, was recorded by Hewitt, 1914, as Muscids.
According to Cotterell, 1920, it lias attacked the
house-fly and blow-fly; in suitable circumstances it might be a
very efficient check on these flies.